package com.bh.utils;

import com.alibaba.druid.util.StringUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import javax.servlet.http.HttpServletRequest;

/**
 * 
 * @author xxj
 *
 */
public class IPUtils {
	private static Logger logger = LoggerFactory.getLogger(IPUtils.class);

	/**
	 * 获取IP地址
	 * 
	 * 使用Nginx等反向代理软件， 则不能通过request.getRemoteAddr()获取IP地址
	 * 如果使用了多级反向代理的话，X-Forwarded-For的值并不止一个，而是一串IP地址，X-Forwarded-For中第一个非unknown的有效IP字符串，则为真实IP地址
	 */
	public static String getIpAddr(HttpServletRequest request) {
        String ip = null;
        try {
            ip = request.getHeader("x-forwarded-for");
            if (StringUtils.isEmpty(ip) || "unknown".equalsIgnoreCase(ip)) {
                ip = request.getHeader("X-Real-IP");
                if (StringUtils.isEmpty(ip) || "unknown".equalsIgnoreCase(ip)) {
                    ip = request.getHeader("Proxy-Client-IP");
                    if (StringUtils.isEmpty(ip) || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) {
                        ip = request.getHeader("WL-Proxy-Client-IP");
                        if (StringUtils.isEmpty(ip) || "unknown".equalsIgnoreCase(ip)) {
                            ip = request.getHeader("HTTP_CLIENT_IP");
                            if (StringUtils.isEmpty(ip) || "unknown".equalsIgnoreCase(ip)) {
                                ip = request.getHeader("HTTP_X_FORWARDED_FOR");
                                if (StringUtils.isEmpty(ip) || "unknown".equalsIgnoreCase(ip)) {
                                    ip = request.getRemoteAddr();
                                }
                            }
                        }
                    }
                }
            }
        } catch (Exception e) {
            logger.error("IPUtils ERROR ", e);
        }
        return ip;
	}
	
}
